In traditional Abyssinia (the historical name of the Horn of Africa), there was no catching fish with hook and line. Instead the parts of different plants that have narcotic effect on fish, and which at the same time do not affect the quality of the meat were used. The principle types of plants employed for this purpose were the Abyssinian euphorbia (Euphorbia abyssinica), the candelabra euphorbia (Euphorbia candelabrum), the ferruginous millettia (Millettia ferruginea), the finger euphorbia (Euphorbia tirucalli), the East African laburnum (Calpurnia aurea), the purple African nightshade (Solanum marginatum), the desert date (Balanites aegyptiaca), and the popcorn senna (Senna didymobotrya or Cassia didymobotrya). The deployment of any of these plants depends on the immediate availability of the plant, the size of the water body in which it is to be employed, and the ease with which they can be prepared into a fishing substance.
In the case of the Abyssinian euphorbia, the candelabra euphorbia, and the finger euphorbia, the milky sap they contain is what is used. It is obtained by wounding or breaking a sprig of the target plant. Its value lies in that it intoxicates the fish exposed to it.
The fruits of ferruginous millettia (Millettia ferruginea) have to be grounded into powder before they can be turned into fishing ingredients. However, as they are highly concentrated they are used for fishing in high-running or undammed rivers and large lakes. The fruits of the desert date also need to be crushed if they are to be used in fishing. They are powerful, and are often employed for killing disease causing worms and mollusks found in water bodies. In the case of the East African laburnum (Calpurnia aurea), the leaves and bark of the plant need to be mashed before their application.
Among the Tigrinya, the Abyssinian euphorbia, the candelabra euphorbia, the ferruginous millettia, the finger euphorbia, the desert date and the East African laburnum were the plants most often employed for freshwater fishing. In the provinces of Gondar, Gojam, Wollo, and Aghewmidir, the bean-like fruits of the ferruginous millettia were the usual ingredients of freshwater fishing. In Showa, the seeds of the purple African nightshade (Solanum marginatum) had primacy. In the southern provinces of Abyssinia, the leaves of popcorn senna were also employed in fishing.
The Tigrinya used the milky sap of euphorbia species mainly for fishing in small streams, when the rivers run very low during the dry season, and in waterholes. In the case of small streams, they were first temporarily dammed below and above the areas where the fish were known to live. Next a quantity of the euphorbia milky sap was put into the water. Then shortly afterwards the fish would be seen to float insensible on the surface of the water.
The English traveller Mansfield Parkyns, who lived among the Tigrinya for three years from 1843 to 1846, described this manner of fishing as “a very profitable way of fishing.” He says that he was astonished at the number of fish caught by a body of men whom he saw fishing in the Mereb River using the sap of Abyssinian euphorbia.
However, today poison fishing is not favored by biologists. The reason is that the substances used for stupefying fish can kill weak water creatures and thereby negatively affect aquatic biodiversity.
References
Parkyns, Mansfield (1853) Life in Abyssinia: Being Notes Collected During Three Years’ residence and Travels in that Country. Volume I. John Murray: London.
Pearce, Nathaniel (1831) The Life and Adventures of Nathaniel Pearce. Edited by John James Halls. Volume 2. Cambridge University Press.
Plowden, Walter Chichele (1868) Travels in Abyssinia and the Galla Country: With an Account of a Mission to Ras Ali in 1848. Edited by Trevor Chichele Plowden. Longmans, Green, and Co.: London.
Harris, William Cornwallis (1844) The Highlands of Ethiopia. 2nd edition. Volume II. Longman, Brown, Green, and Longmans: London.
Neuwinger, H. D. (2004) Plants used for poison fishing in tropical Africa. Toxicon, Vol.44 No.4, pp.417-430. Elsevier Ltd.
Bein, E. and others (1996) Useful Trees and Shrubs in Eritrea: Identification, Propagation and Management for Agricultural and Pastoral Communities. Regional Soil Conservation Unit: Nairobi.
Bekele-Tesemma, Azene (2007) Useful Trees of Ethiopia: Identification, Propagation and Management in 17 Agroecological Zones. RELMA in ICRAF Project: Nairobi.